Motor protection trip class and what it means for your line
The Siemens 3RU2116-1GC1 is a SIRIUS thermal overload relay, size S00, designed to protect motors against overcurrent and phase failure. The overload release is thermal — it uses a bimetallic strip heated by the motor current. This is the traditional, field-proven method that tracks the motor's thermal state without needing a separate power supply for the protection circuit. It compensates for ambient temperature changes between -40 and +60 °C, so the trip point stays accurate whether the panel is in a cold warehouse or a warm machine room.
Wiring and panel fit — spring-loaded terminals, no screw torque to chase
This speeds up panel wiring — no screwdriver torque check, no loosening under vibration — and the connection stays gas-tight over thermal cycling. The auxiliary switch is integrated, so you don't need a separate block for the tripped signal. Size S00 is the smallest SIRIUS frame, so it fits in crowded control cabinets where every millimetre of rail space counts.
Rated motor power and auxiliary contact capacity
At 400 V rated value the relay is rated for 2.2 kW motor power; at 500 V it handles 3 kW; at 690 V it handles 4 kW. This covers direct connection to a PLC input or a contactor coil without an interposing relay in most panels.
Lifecycle and sourcing — current production, no obsolescence worry
For a maintenance planner: this is a relay you can stock one-in-the-cabinet for a 400 V motor line and know it will be available when you need it. No spare, no sleep — but with this part, you can sleep.